Anti-neutrophil cytoplasmic antibodies (ANCA) is autoantibodies characteristic of vasculitis diseases. A connection between ANCA and Wegener's granulomatosis was well established. The interaction of both ANCA phenotypes (PR3-ANCA and MPO-ANCA) with leukocytes provoked cell activation, which might be involved in the pathogenesis of ANCA-related Wegener's granulomatosis.
In this study, we examined whether PR3-ANCA sera and purified immunoglobulins from patients with Wegener's granulomatosis prime human monocytic cells for enhanced responses to microbial components in terms of production of proinflammatory cytokines.
Flow cytometry demonstrated that stimulation with antibodies to proteinase 3 enhanced the expression of TLR2, 3, 4, 7, and 9, NOD1, and NOD2 in human mononuclear cells. The sera and purified immunoglobulins significantly primed human mononuclear cells to secrete interleukin-8 in response to microbial components via TLRs and NODs. Priming effects were also observed for the production of interleukin-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α. On the other hand, PR3-ANCA-negative sera from patients with polyarteritis nodosa which possibly related to MPO-ANCA and aortitis syndrome as well as control sera from a healthy volunteer did not have any priming effects on PBMCs.
In conclusion, PR3-ANCA prime human mononuclear cells to produce cytokines upon stimulation with various microbial components by up-regulating the TLR and NOD signaling pathway, and these mechanisms may partially participate in the inflammatory process in Wegener's granulomatosis.
Anti‐neutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) are highly specific for Wegener's granulomatosis (WG). Evidence for a pivotal role of PR3‐ANCA in the induction of vasculitis has been demonstrated. B cell clusters have been observed within endonasal biopsy specimens.
To determine whether B cell selection and maturation take place in granulomatous lesions of WG.
Granulomatous lesions and the immunoglobulin (VH) gene repertoire from nasal tissue of six WG patients—two active and two smouldering localised WG (ANCA negative, restricted to respiratory tract), plus one active and one smouldering PR3‐ANCA positive generalised WG—were characterised by immunohistochemistry, polymerase chain reaction, cloning, DNA sequencing and database comparison.
B lymphocyte‐rich, follicle‐like areas were observed proximal to PR3 positive cells and plasma cells in granulomatous lesions; 184 VH genes from these granulomatous lesions were compared with 84 VH genes from peripheral blood of a healthy donor. The mutational pattern of VH genes from active WG resembled memory B cells. Structural homologies of VH genes from granulomatous lesions to PR3‐ANCA encoding genes were detected. Significantly more genes (55%, 45%, and 53%, respectively) from active WG compared with the healthy repertoire carried mutations to negatively charged amino acids within the binding site coding regions, favouring affinity to the positively charged PR3.
Selection and affinity maturation of potentially PR3‐ANCA producing autoreactive B cells may start in granulomatous lesions, thereby contributing to disease progression from ANCA negative localised to PR3‐ANCA positive generalised WG.
B lymphocyte; Wegener's granulomatosis; PR3; PR3‐ANCA; VH genes
Wegener’s Granulomatosis is a condition associated with systemic vasculitis which can present with upper respiratory tract symptoms initially. On September 2001, a 15-year-old girl presented with symptoms of nasal block for 3 weeks. She later developed joint pains and worsening renal status requiring dialysis. A renal biopsy was performed which showed pauci-immune cresentric glomerulonephritis. Her cANCA levels were positive. She was treated with oral cyclophosphamide and steroids and later responded.
Wegener granulomatosis; Young girl; Cyclophophamide; cANCA
Subacute bacterial endocarditis (SBE) occasionally exhibits positive cytoplasmic anti-neutrophil cytoplasmic antibody (c-ANCA) of the anti-proteinase-3 (PR-3) type. Clinically, it mimics ANCA-associated vasculitis, such as Wegener's disease with glomerulonephritis. Lung abscesses are the most common manifestation of lung involvement. We herein report a case of culture-negative SBE strongly c-ANCA/PR3-positive accompanied by pulmonary involvement and glomerulonephritis. In this case, we took biopsies of both the lung and kidney, although renal biopsy is usually preferred over lung biopsy. The lung biopsy showed severe alveolar capillaritis, suggesting vasculitis consistent with polyangiitis. The renal biopsy revealed glomerulonephritis with a membranoproliferative pattern. To our knowledge, this is the first such reported case.
A 68-year-old Chinese male patient presented to our hospital with a fever, cough, chest pain, and recurrent peripheral edema. He had a past medical history significant for treated schistosomiasis 20 years previously. Physical examination revealed palpable purpura, mild hypertension, hepatosplenomegaly, and a holosystolic cardiac murmur (Levine 2/6). Echocardiography showed tricuspid valve vegetations with moderate to severe regurgitation. Serum c-ANCA/PR3 and cryoglobulin were strongly positive. Renal biopsy results indicated membranoproliferative glomerulonephritis with several crescents. Chest CT revealed multiple intraparenchymal and subpleural nodules, and lung biopsy showed polyangiitis. The patient’s ANCA titers, glomerulonephritis, and pulmonary injury all resolved after antibiotic therapy.
SBE may present with positive c-ANCA/PR3, multiple pulmonary nodules, pulmonary polyangiitis, and glomerulonephritis clinically mimicking granulomatosis with polyangiitis (Wegener's granulomatosis).
Subacute bacterial endocarditis; PR3/c-ANCA; Granulomatosis with polyangiitis (Wegener's granulomatosis); Glomerulonephritis
Wegener’s granulomatosis (WG) is a necrotizing granulomatous vasculitis characterized by the involvement of the upper or lower airways, lungs, and kidneys, but it can affect almost any organ including the orbit. WG is rare in childhood. This case report describes a 7-year-old girl who presented bilateral idiophatic orbital inflammation and antineutrophil cytoplasmic antibodies-negative titres. Computed tomography scan and magnetic resonance imaging showed enlargement of both lacrimal glands with infiltration. Treatment with corticosteroids achieved remission of the disease. Three years later, she developed a systemic affectation with tracheal stenosis, pulmonary affectation, renal failure, and respiratory tract mucosa inflammation. Lacrimal gland biopsy showed perivascular nonspecific granulomas and ANCA titres remain negative. Treatment with corticosteroids and cyclophosphamide was done. A relapse occurred 2 years later, with complete remission with antitumor necrosis factor-alpha. No other symptoms have appeared after 9 years of follow-up. Early diagnosis and treatment is crucial to increase the survival rate in these patients.
ANCA; children; idiopathic orbital inflammation; exophthalmos; vasculitis; Wegener’s granulomatosis
Wegener’s granulomatosis (WG) is a multisystemic necrotising granulomatous vasculitis of small and medium sized vessels, that primarily involves the upper and lower respiratory tracts, lung tissues and kidneys. Serum antineutrophil cytoplasmic antibodies (ANCA) are a sensitive and specific marker of WG. Whereas the peripheral nervous system is often involved in WG, central nervous system manifestations are reported only in 2–8%, and are rarely present at onset. We report on a patient with atypical neurological presentation of ANCA negative WG in whom the diagnosis was made only after a meningeal biopsy.
A retrospective analysis was conducted of eight cases of Wegener's granulomatosis (WG), who presented with cutaneous lesions. The clinical, immunopathologic and histopathologic features of the cutaneous lesions were reviewed. Antineutrophil cytoplasmic antibody (ANCA) status of the patients was established. When possible, a comparison of immunofluorescence findings of skin biopsies was made with those of renal biopsies taken at the same time. In all except one, systemic and cutaneous disease developed concurrently. On histopathology, leukocytoclastic vasculitis was noted in five patients and features of lupus erythematosus and pyoderma gangrenosum in one case each. Four patients showed immunoglobulin deposits in subepidermal blood vessel walls, while one patient showed granular immune deposits at dermo-epidermal junction only. Immunoglobulin G was the most common immunoreactant detected. C-ANCA/proteinase 3 (PR3)-ANCA was positive in six patients, P-ANCA/myeloperoxidase (MPO)-ANCA in one patient, while one patient did not show ANCA positivity on indirect immunofluorescence. All four renal biopsies showed pauci-immune glomerulonephritis, irrespective of the presence (n=3) or absence (n=1) of immune deposits in the skin biopsy. Skin manifestations are encountered in nearly half of the patients with WG, thus it is important to be familiar with cutaneous histopathologic as well as immunofluorescence findings in WG patients.
Cutaneous biopsy; direct immunofluorescence; pauci-immune
Background. Granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) are autoimmune-mediated diseases characterized by vasculitic inflammation of respiratory tract and kidneys. Clinical observations indicated a strong association between disease activity and serum levels of certain types of autoantibodies (antineutrophil cytoplasm antibodies with cytoplasmic [cANCA in GPA] or perinuclear [pAN CA in MPA] immunofluorescence). Pathologically, both diseases are characterized by severe microvascular endothelial cell damage. Early endothelial outgrowth cells (eEOCs) have been shown to be critically involved in neovascularization under both physiological and pathological condition. Objectives. The principal aims of our study were (i) to analyze the regenerative activity of the eEOC system and (ii) to determine mPR3 and MPO expression in myelo monocytic cells with endothelial characteristics in GPA and MPA patients. Methods. In 27 GPA and 10 MPA patients, regenerative activity blood-derived eEOCs were analyzed using a culture-forming assay. Flk-1+, CD133+/Flk-1+, mPR3+, and Flk-1+/mPR3+ myelomonocytic cells were quantified by FACS analysis. Serum levels of Angiopoietin-1 and TNF-α were measured by ELISA. Results. We found reduced eEOC regeneration, accompanied by lower serum levels of Angiopoietin-1 in GPA patients as compared to healthy controls. In addition, the total numbers of Flk-1+ myelomonocytic cells in the peripheral circulation were decreased. Membrane PR3 expression was significantly higher in total as well as in Flk-1+ myelomonocytic cells. Expression of MPO was not different between the groups. Conclusions. These data suggest impairment of the eEOC system and a possible role for PR3 in this process in patients suffering from GPA.
Wegener's Granulomatosis is a vasculitis of uncertain aetiology. Affected patients usually present with disease of the respiratory and renal tracts. Classic symptoms and clinical findings, together with serology titres positive for anti-neutrophil cytolplasmic antibody against proteinase 3 confirm the diagnosis. Wegener's Granulomatosis can occasionally involve other organs, but solitary parotid gland disease is uncommon; patients generally also have systemic disease.
We report a case of Wegener's Granulomatosis in a 69-year-old Caucasian female presenting initially with an isolated parotid abscess and only subsequently developing nasal, paranasal sinus and respiratory symptoms. We describe the clinical course, diagnostic difficulties, imaging and histopathology of this case.
Major salivary gland infection is not an uncommon ENT disorder, but the clinician should be wary of the patient who fails to respond appropriately to adequate therapy. In such cases a differential diagnosis of Wegener's Granulomatosis should be considered, as early recognition and treatment of this potentially fatal disease is paramount.
Wegener’s granulomatosis (WG) is one form of idiopathic autoimmune vasculitis. The disease has a predilection for the upper and lower respiratory tracts (lungs, nose, sinus), and kidneys. WG may be systemic, severe, and potentially lethal, but it may also be limited to the otolaryngological area or to the eyes and the orbits. Obstruction of the lacrimal pathway is a possible complication of the disease that affects approximately 7% of patients with WG. It usually occurs as a direct extension of sinonasal disease and typically is a late manifestation. Management of such a condition is generally viewed as difficult. We report the case of a patient with a quiescent WG limited to the otolaryngological area. This patient presented a bilateral obstruction of the nasolacrimal ducts caused by bilateral extensive adhesions in the nasal cavity. Because she had several episodes of left-side acute dacryocystitis which necessitated several courses of broad-spectrum antibiotics, she successfully underwent an endonasal endoscopic dacryocystorhinostomy using a diode laser and powered instrumentation. The authors describe the clinical case, the surgical technique, and review the literature.
Wegener’s granulomatosis; recurrent dacryocystitis; endonasal DCR; diode; laser; powered instrumentation
Wegener’s granulomatosis (WG) is a multisystem vasculitic disorder which can commonly afflict various components of the eye. Here we describe some unusual ocular manifestations of the disease in one patient. A young male with history of upper respiratory tract symptoms including epistaxis, nasal stuffiness and maxillary sinus pain presented with bilateral lacrimal gland abscess and ptosis. Lacrimal gland biopsy revealed granulomatous vasculitis. Lung cavities, positive cytoplasmic-antineutrophil cytoplasmic antibodies and high titers of serine proteinase-3 antibodies confirmed the diagnosis of WG. The patient developed dry eyes after a month of first presentation. There was no dryness of mouth, suggesting the absence of salivary gland involvement, and antinuclear antibodies as well as antibodies against Ro and La antigens classical of primary Sjogren’s syndrome were absent. Granulomatous vasculitis of lacrimal gland leading to abscess formation and dryness of eyes has not been described in WG and reflects the aggressive nature of inflammatory process in this disease.
Antineutrophil cytoplasmic antibody; Horner’s syndrome; lacrimal gland; ptosis; Sjogren’s syndrome
Wegener’s granulomatosis, also known as anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, is a small vessel vasculitis with primarily pulmonary, renal, and sinus disease manifestations. The prevalence of Wegener’s granulomatosis is three cases per 100,000 patients. Cardiovascular, neurologic, cutaneous, and joint manifestations have been reported in many case reports and case series. Gastrointestinal manifestations are less noted in Wegener’s granulomatosis, although they have been previously reported in the form of intestinal perforation and intestinal ischemia. Additionally, there are characteristic findings of vasculitis that are noted with active Wegener’s granulomatosis of the small bowel. We report a case of an elderly patient who presented with weight loss, diarrhea, and hematochezia. His symptoms were chronic and had lasted for more than 1 year before diagnosis. Inflammatory bowel disease or chronic enteritis due to Salmonella arizonae because of reptile exposure originally were suspected as etiologies of his presentation. The findings of proteinuria, renal failure, and pauci-immune glomerulonephritis on renal biopsy, in conjunction with an elevated c-ANCA titer, confirmed the diagnosis of Wegener’s granulomatosis with associated intestinal vasculitis. This case demonstrates an atypical presentation of chronic duodenitis and jejunitis secondary to Wegener’s granulomatosis, which mimicked inflammatory bowel disease.
ANCA-associated vasculitis; Wegener’s syndrome; pauci-immune glomerulonephritis; Salmonella arizonae; inflammatory bowel disease
The use of serum antibodies to neutrophil cytoplasmic antigens (ANCA) as a diagnostic marker for Wegener's granulomatosis and other forms of vasculitis has been assessed. Although ANCA have been described by several groups the precise antigenic targets are unknown, and detection of ANCA still relies on an indirect immunofluorescence assay technique. Several different patterns of fluorescence have been produced by using sera from different groups of patients, and insufficient information is available on the frequency of positive results and of the patterns of immunofluorescence obtained when serum from patients with vasculitis as a part of a generalised connective tissue disease is used. A study was carried out on serum from 240 patients, including 23 patients with Wegener's granulomatosis, 12 with microscopic polyarteritis, and 30 with various connective tissue diseases. Three patterns of fluorescence were observed: bright coarsely granular cytoplasmic, bright non-granular cytoplasmic, and weak diffuse cytoplasmic. The bright, coarsely granular pattern was 86% specific for Wegener's granulomatosis in this series and was observed in 18 of 23 cases. Other patterns of fluorescence were found in various conditions and were not of diagnostic value. The technique is simple, inexpensive, rapid, and reproducible.
The glycosylation status of autoantigens appears to be crucial for the pathogenesis of some autoimmune diseases, since carbohydrates play a crucial role in the distinction of self from non-self. Proteinase 3 (PR3), the main target antigen for anti-neutrophil cytoplasmic antibodies (ANCA) in patients with Wegener’s granulomatosis (WG), contains two Asn-linked glycosylation sites. The present study explores the influence of the glycosylation status of PR3 on the PR3 recognition by ANCA in a well characterized population of patients with WG.
Forty-four patients with WG (459 serum samples) who participated in a multicenter randomized trial, were tested by capture ELISA for ANCA against PR3 and deglycosylated recombinant variants of PR3.
The patients were followed for a median of 27 months, and the median number of serum samples per patient was 10. At baseline, the correlation between the levels of ANCA against PR3 and against all the deglycosylated recombinant variants of PR3 were greater than 0.94 (ρ<0.001 for all the comparisons). Longitudinal analyses comparing the levels of ANCA against PR3 versus all the deglycosylated recombinant variants of PR3, using linear mixed models, showed no significant statistical differences (ρ≥0.90 in all cases).
The glycosylation status of PR3 has no impact on its recognition by ANCA in WG.
ANCA; biological markers; glycosylation; proteinase 3; Wegener’s granulomatosis
The prevalence of antineutrophil cytoplasmic antibodies (ANCA)
was studied in 12 children with Wegener's granulomatosis. The serum
samples were taken in the active phase of disease and were screened for
ANCA by indirect immunofluorescence with normal neutrophils and enzyme
linked immunosorbent assay (ELISA) using crude neutrophil extract,
proteinase 3, myeloperoxidase, cathepsin G, lactoferrin, and elastase
as antigens. Of these 12 patients, 10 were positive for ANCA in the
active phase of their illness, and they showed a predominantly
cytoplasmic ANCA staining pattern on indirect immunofluorescence. There
were high titres of ANCA directed against crude neutrophil extract,
proteinase 3, myeloperoxidase, and cathepsin G. IgM isotypes occurred
as commonly as IgG isotypes. Therefore, screening for ANCA is usually
but not invariably positive in children with Wegener's granulomatosis.
Specific diagnosis still relies on clinical and pathological features,
and the value of ANCA in the diagnosis of paediatric Wegener's
granulomatosis requires further study.
There are only a few reported cases about spinal cord involvement with Wegener’s granulomatosis (WG) in the literature. In these cases, the spinal cord is usually indented or compressed by dural and meningeal masses which are characterized by necrotizing granuloma formation and vasculitis. And, it usually cannot be correctly diagnosed. A 53-year-old woman suffered from Wegener’s granulomatosis, in whom the upper thoracic spinal cord compression is the initial manifestation. The surgical biopsy and thoracic laminectomy were performed and the histologic examination was done. This patient was finally diagnosed as WG when the pathologic examination revealed as Wegener’s granulomatosis and the serum antineutrophil cytoplasmic antibodies (ANCA) were reported positive; titers of antimyeloperoxidase (MPO) antibodies were markedly elevated. After treatment with cyclophosphamide and corticosteroids this patient partially recovered from neurological involvement. In a case such as this, careful monitoring of clinical parameters is essential for assessing disease activity with repeated MRI if neurologic status changes. Serial measurement of ANCA titers may also be helpful to establish the diagnosis. Cyclophosphamide and corticosteroids are the agents of choice for induction of remission of WG.
Spinal cord; Wegener’s granulomatosis; Vasculitis
OBJECTIVE—Wegener's granulomatosis (WG) is an inflammatory disorder characterised by granulomatous inflammation, vasculitis, and necrotising vasculitis and is strongly associated with anti-neutrophil cytoplasmic antibodies (ANCA). Activated monocytes/macrophages are present in renal biopsy specimens and participate in granuloma formation by synthesising and secreting a variety of chemoattractants, growth factors, and cytokines. In view of these findings, in vivo monocyte activation was evaluated in patients with WG and the findings related to parameters of clinical disease activity.
METHODS—Monocyte activation was analysed by measuring plasma concentrations of soluble products of monocyte activation, that is neopterin and interleukin 6 (IL6), by ELISA, and by quantitating the surface expression of activation markers on circulating monocytes by flow cytometry.
RESULTS—Twenty four patients with active WG were included in this study. Ten of these patients were also analysed at the time of remission. Twelve patients with sepsis served as positive controls, and 10 healthy volunteers as negative controls for monocyte activation. Patients with active disease had increased monocyte activation compared with healthy controls as shown by increased concentrations of neopterin (p <0.0001) and increased surface expression of CD11b (p < 0.05) and CD64 (p < 0.05). In those patients with increased concentrations of IL6 during active disease plasma concentrations of IL6 decreased during follow up when patients went into remission (p < 0.0001). In addition, neopterin (r = 0.37, r = 0.44), IL6 (r = 0.37, r = 0.60) and CD63 expression (r = 0.39, r = 0.45) correlated significantly with disease activity as measured by the Birmingham Vasculitis Activity Score and C reactive protein values, respectively. Compared with patients with sepsis, all markers of monocyte activation in patients with vasculitis were lower.
CONCLUSION—It is concluded that disease activity in WG correlates with the extent of activation of monocytes, compatible with their role in the pathophysiology of this disease.
Keywords: anti-neutrophil cytoplasmic antibody; monocyte activation; vasculitis; flow cytometry
Wegener's Granulomatosis (WG) is a systemic vasculitis typically associated with antineutrophil cytoplasmic antibodies (ANCAs). A small proportion of patients are ANCA negative, however, and this is more commonly found in individuals with disease limited to the ears, nose, throat, and lungs, who do not have renal involvement. Rituximab is a monoclonal anti-CD20 antibody that has been demonstrated to be effective in the treatment of autoantibody-associated rheumatic diseases, including systemic WG. We report the case of a patient with ANCA-negative WG who responded well to rituximab, illustrating that even in the absence of detectable autoantibodies, B-cell depletion can be effective.
There remains a need for biomarkers to guide therapy in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Our objective was to determine whether measures of platelet activation or inflammation are associated with disease activity in Wegener’s granulomatosis (WG).
Study subjects were participants in a clinical trial. Soluble CD40 ligand (sCD40L), C-reactive protein, interleukin 6 (IL-6), IL-8, monocyte chemoattractant protein 1 (MCP-1), P-selectin, vascular endothelial growth factor, and proteinase 3 (PR3)-specific ANCA were measured by ELISA using plasma samples obtained at baseline (active disease), at remission, and prior to, during, and after first flares. Disease activity was assessed by the Birmingham Vasculitis Activity Score for WG (BVAS/WG). Association of biomarkers with disease activity was determined with conditional logistic and linear regression.
Over a mean followup of 27 months, 180 subjects underwent 2044 visits; markers were measured in 563 samples. Longitudinally, all markers other than IL-6 were associated with disease activity. The strongest associations for active disease at baseline versus remission were observed for sCD40L (OR 4.72, 95% CI 2.47–9.03), P-selectin (OR 6.26, 95% CI 2.78–14.10), PR3-ANCA (OR 9.41, 4.03–21.99), and inversely for MCP-1 (OR 0.36, 95% CI 0.22–0.57). BVAS/WG increased by 0.80 (95% CI 0.44–1.16), 0.83 (95% CI 0.42–1.25), and 0.81 (95% CI 0.48–1.15) per unit-increase in PR3-ANCA, sCD40L, and P-selectin, respectively; and decreased by 1.54 (95% CI 0.96–2.12) per unit-increase in MCP-1.
Cytokines arising from within the circulation, including those of platelet activation, correlate with disease activity in WG.
VASCULITIS; BIOMARKERS; DISEASE ACTIVITY; WEGENER’S GRANULOMATOSIS
BACKGROUND—Wegener's granulomatosis (WG) is considered a pauci-immune systemic vasculitis based on the absence of immune deposits in renal biopsies of patients with active disease. In animal models of antineutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis, immune deposits along the glomerular capillary wall are present at early stages of lesion development. These deposits are degraded rapidly, resulting in "pauci-immune" lesions.
OBJECTIVE—To test the hypothesis that immune deposits can also be detected in early lesions of patients with WG, thereby initiating an inflammatory reaction that, in time, is augmented in the presence of ANCA, resulting in pauci-immune lesions later on.
METHODS—The presence of immune deposits in skin biopsies taken within 48 hours of lesion development was investigated. Direct immunofluorescence was used to examine 32 skin biopsies for the presence of immune deposits (IgG, IgA, IgM, C3c). When possible, a comparison was made between the immunofluorescence findings in renal and skin biopsies taken at the same time.
RESULTS—Four of 11 biopsies taken at initial presentation and four of 21 biopsies taken at the onset of a relapse of WG showed IgG and/or IgA containing immune deposits in the subepidermal blood vessels. All nine renal biopsies showed pauci-immune glomerulonephritis, irrespective of the presence (n=5) or absence (n=4) of immune deposits in the skin biopsy.
CONCLUSION—A substantial number of skin biopsies showed immune deposits during active disease. These results could support the hypothesis that immune complexes may trigger vasculitic lesions in WG.
Wegener granulomatosis (WG) belongs to the heterogeneous group of systemic vasculitides. The multifactorial pathophysiology of WG is supposedly caused by yet unknown environmental influence(s) on the basis of genetic predisposition. The presence of anti-neutrophil cytoplasmic antibodies (ANCA) in the plasma of patients and genetic involvement of the human leukocyte antigen system reflect an autoimmune background of the disease. Strong associations were revealed with WG by markers located in the major histocompatibility complex class II (MHC II) region in the vicinity of human leukocyte antigen (HLA)-DPB1 and the retinoid X receptor B (RXRB) loci. In order to define the involvement of the 6p21.3 region in WG in more detail this previous population-based association study was expanded here to the respective 3.6 megabase encompassing this region on chromosome 6. The RXRB gene was analysed as well as a splice-site variation of the butyrophilin-like (BTNL2) gene which is also located within the respective region. The latter polymorphism has been evaluated here as it appears as a HLA independent susceptibility factor in another granulomatous disorder, sarcoidosis.
150–180 German WG patients and a corresponding cohort of healthy controls (n = 100–261) were used in a two-step study. A panel of 94 microsatellites was designed for the initial step using a DNA pooling approach. Markers with significantly differing allele frequencies between patient and control pools were individually genotyped. The RXRB gene was analysed for single strand conformation polymorphisms (SSCP) and restriction fragment length polymorphisms (RFLP). The splice-site polymorphism in the BTNL2 gene was also investigated by RFLP analysis.
A previously investigated microsatellite (#22.214.171.124, Santa Cruz genome browser (UCSC) May 2004 Freeze localisation: chr6:31257596-34999883), which was used as a positive control, remained associated throughout the whole two-step approach. Yet, no additional evidence for association of other microsatellite markers was found in the entire investigated region. Analysis of the RXRB gene located in the WG associated region revealed associations of two variations (rs10548957 pallelic = 0.02 and rs6531 pallelic = 5.20 × 10-5, OR = 1.88). Several alleles of markers located between HLA-DPB1, SNP rs6531 and microsatellite 126.96.36.199 showed linkage disequilibrium with r2 values exceeding 0.10. Significant differences were not demonstrable for the sarcoidosis associated splice-site variation (rs2076530 pallelic = 0.80) in our WG cohort.
Since a microsatellite flanking the RXRB gene and two intragenic polymorphisms are associated significantly with WG on chromosome 6p21.3, further investigations should be focussed on extensive fine-mapping in this region by densely mapping with additional markers such as SNPs. This strategy may reveal even deeper insights into the genetic contributions of the respective region for the pathogenesis of WG.
Proteinase-3 (PR-3) is a neutral serine proteinase present in azurophil granules of human polymorphonuclear leukocytes and serves as the major target antigen of antineutrophil cytoplasmic antibodies with a cytoplasmic staining pattern (c-ANCA) in Wegener's granulomatosis (WG). The WG disease appears as severe vasculitis in different organs (e.g. kidney, nose and lung). Little is known about the expression and distribution of PR-3 in the lung. We found that PR-3 is expressed in normal lung tissue and is upregulated in lung tissue of patients with WG. Interestingly, the parenchymal cells (pneumocytes type I and II) and macrophages, and not the neutrophils, express PR-3 most strongly and may contribute to lung damage in patients with WG via direct interaction with antineutrophil cytoplasmic antobodies (ANCA). These findings suggest that the PR-3 expression in parenchymal cells of lung tissue could be at least one missing link in the etiopathogenesis of pulmonary pathology in ANCA-associated disease.
granuloma; in situ hybridization; pneumocytes; proteinase-3; Wegener's granulomatosis
Wegener’s granulomatosis (WG) is one of the most common small- and medium-sized necrotizing vasculitides that mainly affects the upper and lower respiratory tract and the kidneys. Cardiac manifestations in WG are relatively rare, and their role and place among different causes of mortality remain largely unknown. Substantially increased number of reports describing involvement of all structures of the heart, which underlie conduction disturbances, valvular disease, ischemic heart disease and other potentially serious conditions, underscores importance of comprehensive cardiovascular investigations and monitoring of patients with WG. The majority of previous reports and our current observation distinguish coronary vasculitis and thrombosis as a cause of myocardial ischemia and cardiovascular co-morbidities in WG. It seems plausible that inflammatory processes in this disease, like in some other systemic vasculitidies, do not predispose to accelerated atherogenesis. However, characteristic small- and medium-sized vasculitis still can manifest as myocardial ischemia and infarction. We overview diverse cardiac manifestations and present our own rare case of angina in the oligosymptomatic debut of WG. Importantly, in this case, coronarography failed to reveal atherosclerotic disease or thrombotic occlusion. However, magnetic resonance imaging (MRI) with adenosine test revealed subendocardial ischemia. As a result of immunosuppressive therapy with a steroid and cyclophosphamide, myocardial ischemia disappeared.
Wegener’s granulomatosis; Coronary arteries; Atherosclerosis; Vasculitis.
Wegener's granulomatosis is a disease characterised by a necrotising vasculitis and granulomatous inflammation. The localised form involves the upper and/or lower respiratory tracts while in the commoner generalised form there is a widespread necrotising vasculitis and renal involvement. Intestinal involvement, which may be severe, has been detected at necropsy in 24% of cases. Gastrointestinal symptoms are uncommon, however, none being mentioned in a recent series of 87 cases. There has been only one reported case of intestinal perforation secondary to Wegener's granulomatosis. We report a case of small and large bowel perforations in a patient with Wegener's granulomatosis.
Rationale: Standard therapy for Wegener's granulomatosis is fraught with substantial toxicity and not always effective. B lymphocytes have been implicated in the pathogenesis of Wegener's granulomatosis. Their depletion has been proposed as salvage therapy for refractory disease. Earlier encouraging reports are confounded by concomitant immunosuppressive medications and include only limited available biomarker data.
Objectives: To evaluate the efficacy and safety of rituximab for remission induction in refractory Wegener's granulomatosis.
Methods: A prospective open-label pilot trial was conducted with 10 patients monitored for 1 yr. Included were patients with active severe antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis, ANCA positivity, and resistance to (or intolerance of) cyclophosphamide. The remission induction regimen consisted of oral prednisone (1 mg/kg/d) and four weekly infusions of rituximab (375 mg/m2). Prednisone was tapered and discontinued over 5 mo. Failure to achieve remission, a clinical flare in the absence of B lymphocytes, and inability to complete the glucocorticoid taper were considered treatment failures.
Main Results: Three women and seven men (median age, 57 yr; range, 25–72 yr) were enrolled. All had ANCA reacting with proteinase-3. The median activity score at enrollment was 6 (range, 5–10). All patients tolerated rituximab well, achieved swift B-lymphocyte depletion and complete clinical remission (activity score, 0) by 3 mo, and were tapered off glucocorticoids by 6 mo. Five patients were retreated with rituximab alone for recurring/rising ANCA titers according to protocol. One patient experienced a clinical flare after B lymphocyte reconstitution.
Conclusion: In this cohort, rituximab was a well-tolerated and effective remission induction agent for severe refractory Wegener's granulomatosis.